What is Syphilis?

Syphilis is a bacterial infection that initially causes skin sores, rashes and ulcers to form on the genitals, skin, and mucus membranes. Although this infection is curable, it can be fatal if it is not treated quickly. If left untreated, syphilis may cause permanent damage to other organs, such as the brain and heart.

Syphilis is caused by a bacterium called Treponema pallidum. There are four different stages of syphilis: primary, secondary, latent, and tertiary. The disease is contagious during the primary and secondary stages, and sometimes, the latent period.

Most cases of syphilis are transmitted during oral, anal, or vaginal sex. A patient may also acquire the infection if his/her blood comes into contact with an infected patient's blood. It may also be transmitted through direct contact with an infected person's skin sore. An infected pregnant woman may also transmit the infection onto her fetus during pregnancy. This is because the mother's infected blood passes through the placenta and to the baby.

Treponema pallidum is not able to survive outside of the body. Therefore, the disease cannot be transmitted by sharing clothing, toilet seats, or other objects with an infected person.

Syphilis Symptoms

Symptoms of syphilis vary with each stage. Initial symptoms during the primary stage typically develop 10 days to three months after exposure. Symptoms commonly include enlarged lymph nodes near the groin and a small painless chancre sore on the part of the body where the bacterium was transmitted. Chancre sores are most common on the tongue, lips, genitals, or rectum. Some patients may develop several sores. If patients do not receive treatment, the symptoms will go away on their own within three to six weeks. However, this does not mean that the infection is gone. In fact, it means that the infection is progressing to the secondary stage.

Symptoms of secondary syphilis develop two to 10 weeks after the first chancre sore appears. Symptoms may include a skin rash that causes small reddish-brown sores, fever, fatigue, general feeling of discomfort, soreness, and aching. If the patient does not receive treatment during this stage, symptoms may go away within a few weeks or repeatedly go away and come back for as long as one year. Even if symptoms are not present, the infection will continue to worsen without treatment.

Some patients experience a period called latent syphilis before tertiary symptoms develop. During the clinical latency stage, no symptoms are present. This stage may last one to two years. The tertiary stage may develop immediately after the secondary stage or one to two years after the latent stage. This is the final and most severe stage of the infection. During the tertiary stage, syphilis may cause permanent organ damage and death. It often causes brain (neurological) problems, which may include stroke, infection and inflammation of the membranes that surround the brain and spinal cord (meningitis), numbness, poor muscle coordination, deafness, visual problems or blindness, changes in personality, and dementia. Syphilis may also affect the heart, causing bulging (aneurysm) and inflammation of blood vessels, including the aorta, which is the body's main artery. It may also cause valvular heart disease, such as aortic valve stenosis (when the valve becomes narrowed). All of these symptoms are potentially life threatening.

Babies born with syphilis may develop symptoms that are apparent at birth or several weeks after birth. Syphilis progresses much quicker and is more likely to cause complications in infants than adults. If the baby does not receive prompt treatment, serious and life-threatening complications may develop. Symptoms may include bone abnormalities, depressed nose bridge (saddle nose), vision and hearing problems (that may lead to deafness or blindness), swollen joints, screwdriver-shaped teeth (Hutchinson's teeth), and scarring where chancre sores developed.

Complications from Syphilis

In general, patients with syphilis have an increased risk of developing the human immunodeficiency virus (HIV). This is because a syphilis chancre sore provides an easy way for HIV to enter the body.

Syphilis Diagnosis

In order to prevent life-threatening complications of syphilis, patients should be tested if they have symptoms of syphilis or suspect that they were exposed to syphilis. Doctors recommend annual STI screenings for patients who have increased risks of developing STIs. This includes patients who have multiple sexual partners, engage in unprotected sex, or who have sexual partners who have or have previously had an STI. Routine testing is especially important for detecting syphilis because symptoms may come and go.

If the patient has sores that are characteristic of syphilis, a healthcare provider may scrape a small sample of cells from affected skin. The cells are then analyzed under a microscope for the presence of Treponema pallidum. If the bacterium is present, a positive diagnosis is made. If patients do not have sores, a blood test may be used to diagnose syphilis. A sample of blood is taken from the patient and analyzed for antibodies to the bacterium that causes syphilis. These antibodies are proteins that are specialized to detect and help destroy the bacterium. If the antibodies are present, a positive diagnosis is made.

If it is suspected that the infection has spread to the brain, a healthcare provider may recommend a test called a lumbar puncture. During the procedure, a long thin needle is inserted into the lower back. A small sample of fluid from the spine (cerebrospinal fluid) is removed and analyzed under a microscope for the disease-causing bacteria.

Syphilis Treatment

If treated early, patients with syphilis can expect a full recovery. Patients receive one to three injections of an antibiotic called penicillin. This medication kills the bacterium and cures syphilis. Even if a pregnant mother receives treatment for syphilis, the newborn should also receive antibiotics as a precautionary measure. Patients should avoid sexual contact with their partners during treatment in order to prevent transmitting the infection.

During the first day of antibiotic treatment, many patients experience the Jarisch-Herxheimer reaction. Researchers believe that this reaction occurs because so many bacteria are dying at once. Symptoms, which usually only last one day, may include fever, nausea, aching pain, and headache.

Sexual partners of patients who have been diagnosed with syphilis should be tested and treated for STIs.

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